Perhaps you should try some spelling variations:
ban hang » ngan hang
chat hoc » chat hoa, chat thom, cho hoc
te sach » toc sach
sach ky » sac ky, sach y, sach ty
va tinh » may tinh
cao duc » dao duc, cao suc, giao duc
cao hoc » co hoc, cho hoc
hieu ve » hieu va, hieu van
cua tre » cua te, cuu tre, cua triet
ve cao » va cao, ve bao, ve cac
di cua » dai cua, doi cua, de cua

You may be able to get more results by adjusting your search query.

• Performing a fuzzy search may retrieve terms with similar spellings: te sach ky nang ((cao hoc) OR (chat hoc)). hieu ve cao duc ((ban hang) or (va tinh)) di cua tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: te sach ky nang ((cao hoc) OR (chat hoc)). hieu ve cao duc ((ban hang) OR (va tinh)) di cua tre*.
• The words AND, OR and NOT may confuse the search; try adding quotes: "te sach ky nang ((cao hoc) OR (chat hoc)). hieu ve cao duc ((ban hang) or (va tinh)) di cua tre*".